Investigators say the fire was set.
Police say Qua-Daishia Hopkins' mother had testified against a man who was convicted last year of running a crack house next to their home.
Prosecutors said at Isaac "Chin" Barlow's trial that there was evidence he was trying to locate witnesses so he could "get rid of them."
Francis Hopkins was on the list.
Still, authorities have not named any suspects or ruled out any motives in Sunday's fire.
